Core for tire vulcanization



'l1 MDGLEY ET AL EURE FOR TIRE VULCANZZATGH ggil Filed Sept. 24, 1,921

uff? 0 L LS? J' N VEN T0125 Patented Mar. 16, 1926.

UNITE@ STATES THOMAS lVIDGLEY, OF HAMPDEN, MASSACHUSETTS, PASADENA,CALIFORNIA, .ASSIGNORS TO THE FTSE `PEE FALLS, MASSACHUSETTS, ACORPOR-ATON OF AND Ranieri B. nnxfnon, on RUBBER COMPANY, on onloo-MASSACHUSETTS..

CORE FOR TIRE VULCANIZATON.

Original application led September 24, r1921, Serial No. 503,320.Divided and this application 'led September 10, 1925.

To all whom t may concern.'

Be it known that we, THOMAS hllrnonnr, residing at Hampden, county ofHampden, State of Massachusetts, and RALPH B. NAY- Lor., residing atPasadena, county of lios Angeles, State of California, both beingcitizens of the United States, have invented certain new and usefulimprovements in Cores for Tire Vulcanization, of which we declarethefollowing` to be a full, clear, and exact description. l

This invention relates to improvements ni cores on which tire casingsare manufactured, and is a division of an application tiled by usSeptember 24, 1921, Serial No. 503,020, which claims a process ofmanufacA ture in which these cores are used.

For a more complete disclosure of the invention reference is made to theaccompanying drawings, in which t Fig. 1 is a sectional view of a tirecasing in which the stippled portion represents 1n a general way theapproximate degree of partial vulcanization which may be given to thetire casing while the heat is applied to it from the inside;

Fig. 2 is a like view but showing by the stippling how the tire may becompletely vulcanized after the molds have been closed on the' coveringrubber and heat applied through them to the tire casing;

Fig. 8 is a sectional and detail view of a vulcanizing pot in which thisparticular species of invention can be carried out to advantage; and

Fig. 4 is a plan view of thetire vulcanizing core used in carrying outcertain features of the invention.

In Fig. 3 is shown a heater fitted up with means for maintainingseparation of the mold members as long as desired, or until the regionalor partial vulcanization through the carcass asindicated in Fig. 1iscompleted.

rI`he heater comprises a cylinder 50 mounted on a casting 51, supportedon a foundation 52. To cylinder 50 is secured a head 53 with inwardlyprojecting` lugs 54 under which a removable cover 55 is held. Movablethrough the foundation and the casting 51 is a hydraulic plunger 56,under which water pressure is introduced by any suitable means. A table57 is carried on the Serial No. 55,420.

flanged top of plunger 56. By controlling` the water pressure under thelplunger the table may be raised and loweredand a pile of molds andtiresk placed on the table can be pressed with any desired force againstthe cover 55. Leakage of water pastthe plunger 56 is prevented bystufling boxes 58 and 59. Provision is made, as by an inlet 60, andoutlet 61, for furnishing compressed air, steam or water to the insideof the heater. All the above parts are old and well known in the art andneed not be described further.

The tire casings are mounted on internally chalnbered ring cores. Thesecores may be the ones on which the casings were constructed. Hollowcores such as core 13, if the tire casing is of the type havinginextensible beads, may be formed of a plurality of sections heldtogether by suitable means in a well known manner. Provision is made forthe circulation of steam through the several hollow sections by anysuitable steam connections. If the tire casings are of the clincher orextensible type the hollow cores may be integral, having a partitionwall 85 between adjacent inlet and outlet passages 86 and 87 foradmitting ,steam or heating fluid to the interior. l l l Connectionvismade to the hollow interior of the cores through flexible pipes, as byan inlet pipe 62 connected to the top core by a short pipe v63. rlhechambers of the several cores are joined by flexible tubes 64, and thebottom core is connected to an Outlet by a flexible tube 65. In thismanner the A connections of inlet pipe and outlet pipe to each coreprovides for a circulation inthe cores.- By this circulation the coresmay be maintained at a desired temperature so as to apply heat to theinterior of the 'tirelcasing while the outside of the casing is exposed.Y

f Surrounding each core is a split mold composed of an upper section 67and a lower section 68. These sections are guided rela` tive to eachother by ydowels 69 lfastened. in the lower section and running in holesVin the upper section. Each section has an inwardly projecting annularlug 70 by which the sections of each mold are held 'apart as will bedescribed. The forming faces of the mold sections are shaped to give thedesired form to the tire, and may be provided with the usual raised anddep qessed portions to give a design as indicated in Fig. 2, althoughsuch patternV has not` been shown in Fig. 3.

Fitting between ilanges 66 of the cores and lugs 70 of the molds aredouble wedges 71 which, when held outwardly, will hold the mold sectionsapart a distance, out of contact with the casing according to the designof the wedges 7l, and will position the core midway between them. rlhesewedges form part of what may be termed a toggle unit. One toggle unit isprovided for each of the split molds, and preferably there are threewedges, equally spaced circumferentially, to each unit. Each wedge ispivoted by a pin to a pair of arms 72 which straddle an inwardlyextending lug on the wedge. The other ends ofthese arms are pinned to alug on head 73. Head 73 is provided with a Hange 74 which serves as anabutment to prevent the arms 72 swinging upwardly beyond the positionshown. In this position the arms are slightly higher than the line oftheir pivots on head 73, and hence, once they have been placed in thisposition, the pressure exerted by the mold sections on the wedges willprevent the arms swinging downwardly past the line of their `pivots andthe breaking of the toggle thus formed.

The thickness of head 7 3 is preferably such that, when the molds andtoggle units are stacked on top of one another, a slight space will beleft between adjacent heads as` shown in the drawing. This is to allowthe toggles to be broken one at a time by the mechanism about to bedescribed. Running in a bearing in table 57 is a block 75, whose bottomrests upon rollers 76 at the ends of bell cranks 77, and whose top isarranged to abut against the lowest head 7 3. rlhe other end of eachbell crank 77 is connected by a link 78 to another bell crank 79 pivotedto the table 57. The lower end of bell crank 79 is formed into a tubularsleeve 80, in which runs a spring pressed pawl 8l. rl`he outer end ofthis pawl is adapted to engage a vdepending lug 82 attached to casting5l. VVhen the parts are in the position shown in the ligure, the pile ofmolds reaches nearly to the cover and in this -type `of heater the moldpressure for the iinal vulcanization is obtained by forcing the pileagainst the cover by the hydraulic plunger 56. As the plunger is raisedthe outer ends of pawls 8l catch under the lugs 82 and cause the innerends of bell cranks 77 -to be raised, thus raising the block 7 5. Asthis block abuts against the -lowest head 7 3 the latter is raised,swinging toggle arms 72 past their dead center. When the toggle is thusbroken the weight oi the molds, piled on top of the bottom sec` tion ofthe lowest one, will force the wedges of that one inwardly, thus:forcingthe lowest head 73 upwardly until it impinges against the secondfrom the bottom head. :in this manner the breaking of the togglesproceeds successively from bottom to top oi the pile. It desired thespace between heads 73 may be decreased by thickening the heads enoughto Contact so that all the toggles will be broken substantiallysimultaneously by the raising oic block 75, but the present constructionis preferable in this instance where the molds are held out of contactwith the casings, as it avoids heavy shock due to the simultaneouscollapse of all the molds, which are very heavy. lt will be noted thatthe molds may be collapsed and the vulcanizing pressure applied withoutremoving the cover from the heater. This both saves time and avoidscooling` of the molds and casings with consequent loss of heat andinterruption in the vulcanizing process. Instead of using the moldmanipulating means described the invention could be carried out byopening the heater and applying the molds to the casings by hand, orother ways. rllhe apparatus described is for convenience.

A plate 83 with a cutaway portion Sei is placedon the top of the pile ofmolds to allow pressure to be exerted by the pile against the cover 55without injuring the pipe 62.

On the descentof the plunger 5G pawl's 8l will slip by lugs 82 onaccount of their spring mounting. Il the plunger is raised with no moldsupon it, or with a pile not reaching to the top o't the heater, the:pawls will be engaged by the lug as described and will break thetoggles of whatever units are supported by the plunger, but will thentilt past vthe lugs and allow t-he `plungerrto ascend freely.

Having thus described our invention, we claim:

A tire vulcanizing core, `a tubular annulus havinga partition thereinand having a continuous passage throughout its circumferential extentfrom one side to the other side of said partition, a fluid-inlet at oneside of and adjacent to said partition, and a Huid-outlet at the otherside of and adjacent to said partition, said fluid-outletand fluid-inletextending inwardly of the core, so vthat these fluid carrying` elementsextend between the beads of the tire casing when the core is in thecasing, and so that the current of fluid can be el'l'ected substantiallythrough the circumferential extent of the core for the purposespecified.

THOMAS MIDGLEY. RALPH B. NAYLOR.

